Rivet and method of applying the same



Dec. 19, 1939;

" C. W. CHERRY RIVET AND METHUD'OF' APPLYING THE SAME Filed June 21,19:57

. INVENTOR. I

0424 W ovEere vBY ATTORNEY.

Patented UNITED STATES PAT-em, OFF-ICE .luvr-i'r m lulmion or srruma Tim"SAME a r c iw. cherry. camel, Ap ilsiii iiii June :1, 1937, Serial No."149,331v

' Claims. (Cl. 218-29) This invention relates to rivets and method ofriveting.

An object of" the invention 'is to provide a method whereby rivets,bolts,"stays, or the like,"

.5. can be readily fastened inpla'ce' in objects without hammering, orwithout any necessity for backing.

Another object'ofthe invention is ,to provide v a method for rivetingwhereby hollow or tubular rivets, bolts, -stays orthe like can befastened the objects fastened together.

A further object. ofthe invention is to'provide in place by easymanipulation from one side of a rivet or the like whiclimay be fastenedin place-by an apparatus applied stem end of the rivet or from one sideof. plates-to be riveted and whereby hammering and backing is entirelyobviated.

; A further. object of the invention is to provide a method whereby ahollow rivet can be fastened in place by forces exerted and trans-'mitted from one side of the rivet through the passage in the rivet tosimultaneously-press on a both ends of the rivet.

Another object of 'this invention is to provide a method for rivet ng.which is highly useful and simple in construction. Convenienceofarrangement, lightness andcomparative' inexpense of manufacture arefurther objects which have been 80 home in mind in the production anddevelop- V ment of the invention.

I am aware that some changes may be in the. general arrangements andcombinat ons of the several devices and parts,- as well as in viilithedetails of -the'constructionj thereof without.

departing from thescop'e of the present-invention" as set forth in thefollowing specification,

- and asdeflnedi'n the following claimsy-hence I I the accompanyingdrawing.

. which will be 'msde' sniie i'i the following detailed description andspecifically pointed out] in the a pended-claims, referenceis had totheaccompanying drawing for the illustrative em-' bodiment of theinventiomwherein; 1

Figure -1 isadetail side. view of the former shank of my rivet. 7 I

. Figure 2 is asectionaldetail view of a hollow rivet.

the

Figure 3 is an assembled view of the rivet and shank,'partly in section.e Figure '4 is'an assembled view of the rivet and shank in plates to bejoined.

Figure 5 is a partly sectional view of the rivet s in place as the rivettail is formed. v

Figure 6 is a sectional viewer the completed rivet Joint.- I a Figure 7is a partly sectional view of the riveted joint, showing the shankbroken. I 10 Figure 8 is an assembled view of a rivet with another formof former shank.- i Figure 9 is a sectional view of the riveted Jointshowing the former shank broken. i L

Figure 10 is a partly sectional view of an as- 16 I sembled rivet, andanother modified former shank.

Figure 11 isa fragmental, somewhat diagrammatic sectional viewof ariveting apparatus for my rivet. z 20 In my method of applying rivetsthe first step is the placing of a hollow rivet into the-holes of theobjects to be fastened together. The second step is the simultaneousapplication of pres-' sure to both ends of the rivet to a degree to 25press the opposed ends of the rivets against the opposite'sides of saidobjects so asto hold the same fast together- The force for said opposedpressure at both ends of the ,rivetis preferably applied from one endonly of the rivet 'but is I ha mitted through the passage'in the rivetto ther end. The force is transmitted to the farther end of the rivet byan element .adapted to automatically limit pressure to a predeter--' mined degree. For instance this last step'may 3s vbe accomplisheduby theuse of a tension memher-the elasticlimit of which is such that saidmember breaks when'agiven pressure is reached between the opposed endsof-the rivet. v I in connection with my methods in the h'ereinillustration atiibular rivet 20 with a rivet head 2| preformed at oneend thereof. Through the-passage 22 of the rivet is extended the shank23 of a former 24, so that the former 24 is opwith thrforegomg-andothersjobjtsimweir posite the tail point- 26 ofthe 'rivet 20. when-4sthe rivet is thus assembled it is placed infthealigned holes 21 of 'thobjects tobe fastened.

-together-,such as for i "tance of plates 28. It is.

' diameter thanthat cf-the r'ivetlzo'. This bevel or'miter onthe' former24 determines'the angle and shape to which the tail point 261s spread.

flliereforeform'ers of various shapes and des5 signs may be employedaccording to the type of shown in Figure has a flattened enlargedpulling end 33 formed after the shank 32 is assembled through the rivet28 for engagement by a suitable gripper. In all forms of shanks a. lineof constriction may be provided in the form of an indent or groove 30,as shown in Figures 8 and 9 to determine the location of the breakingpoint of the shank.

In operation the shank 23, 29, or 32, is gripped at its free end and apull is exerted thereon so as to force the former 24 against and insidethe tail point 26 so as to spread the tail point 28 and form a suitablyshaped rivet tail 34 pressed the adjacent plate 28. It is preferableagainst that pressure be exerted on the rivet head 2| simulta'neousiywith the pulling force on the former shank. In other words the leveragefor the pulling force on the former die is fulcrumed or borne bypressure on the rivet head 2|.

A riveting apparatus to accomplish the aforesaid steps of riveting isillustrated in ,Figure 11.

In this apparatus an outer cylinder or casing 38 has a seat or dolly 31,that fits over the exterior of the rivet head 2|. A shank holder 38 isslidable within the casing 38 and is prevented from turning by a setscrew 39 which is extended from the casing 38 into a longitudinal keyslot 4| on the holder 38. Both the outer casing 36 and the inner holder38 are cut away at one side near the dolly 31 so as to form an inlet 42for the introduction of the rivets and shanks into the apparatus. Theholder 38 is provided at its inner end for a suitable engagement elementwith the former shanks. The holder 38 in the embodiment shown in Figure11, has a shouldered end 43 fitting under the shank head 3|.

In operation the casing 38 is pressed against the rivet head 2| andsimultaneously the shank holder 38 is pulled outwardly of the casing 38and away from the rivet head 2| 'so as to pull the former 24 against andinto the point 28 ofthe rivet until said point is spread into a rivettail. The extent of tension may be regulated by the stroke of the holder38. If it is desired the former shank may be left within the fastenedrivet to fill the rivet passage 22. However, by having former shanks ofequal strength the same may be designed for a suitable uniform, ultimatestress so as-to' break when the rivet isfast, and the broken pieces thenreadily fall out of the rivet passage 22. In this latter event, ifnecessary, the rivet passages 22 may be filled with metal cement, or theaforesaid tapered metal pin, or the like after the riveting iscompleted.

The apparatus may be operated manually, or

' hydraulically, or electrically. For the purpose of illustration in theembodiment in Figure 11 a pair of cams 43 are fulcrumed each to anopposed point 28 until the rivet is fastened.

ture.

The extent of pressure exerted in forming the tail of a rivet isdetermined by the breaking of the shanks, which are preferably made ofuniform elastic limit so as to break at the same ultimate stress. Butthe same may be also determined by the length of the stroke to which theformer shank is pulled. This can be also'accomplished by releasing thegrip on the shank of the former after a predetermined stroke.

Having thus described my invention what I now claim and desire to secureby Letters Patent is:

1. As an article of manufacture, a rivet assembly comprising, a hollowrivet, a preformed head at one end of the hollow rivet, a tension memberslidable in the passage of the hollow rivet, a former on the tensionmember adjacent the tail of the rivet and extending into said tail forspreading the tail. outwardly into fastening position when pulled bysaid tension member, and an enlarged head formed integrally on theportion of the tension member outside said head whereby an axial pullingforce can be applied to said tension member, said tension member havingan area of predetermined reduced tensile strength where the tensionmember yields and breaks after the forming of the rivet tail to apredetermined flare.

2 As an article, of manufacture, a rivet assembly comprising, a hollowrivet, a preformed head 'at one end of the hollow rivet, a tensionmember in the passage of the hollow rivet, a former on the tensionmember adjacent the tail of the rivet,for spreading the tail intofastening position when pulled by said tension member, and an. enlargedhead formed integrally on the portion of the tension member outside saidhead whereby an'axial pulling force can be applied to said tensionmember, said tension member being adapted to break and release from thehollow rivet after the forming of the rivet tail to a predeterminedbutfully fastening flare so that said holshank slidably extended throughthe hollow rivet,

a forming head on the shank at the unformed tail of the rivet, a gripportion formed integrally on the shank outside the rivet head wherebythe shank can be gripped for axial pulling of the shank and said forminghead against the tail of the hollow rivet for forming said tail, saidgrip portion being wider than the passage in the rivet.

4. The method of riveting which consists in providing a rivet having anaperture through from its head to its tail, slidably assembling atension member through said rivet, said tension member having a fixedformer head thereon for forming a head on thetail end of the rivet,forming an engagement head on the tension member outside of the head ofthe rivet, introducing the rivet and its tension member together throughan opening in a structure with a portion of the rivet and tension memberextending beyond both sides of the structure, applying an axial force tothe engagement head of the tension member and also applying areactionary axial force simultaneously and continuously to the head ofthe rivet until after a rivet head is completely formed at the tail endof the rivet and the rivet is secured to said struc- 5. The method ofriveting which consists in providing a rivet having an aperture throughfrom.

its head to its tail, slidably assembling a tension member through said'rivet, said tension member having a fixed formerlhead thereon forforming a head on the tail end of the rivet, forming an engagementheadon the tension member outside 0! the head of the rivet, introducingthe rivetand its tension membertogether through an opening ina structureapplying an axial force to the engagement ead of the tension member andalso applying a, re tionary axial force to the heed oi the rivetsimultaneously and continuously until ing oi. the tensionmember, andthen releasing the entire broken tension member from the rivet.

CARL w. cnnnrm

